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From: Adam Beneschan <adam@irvine.com>
Newsgroups: comp.lang.ada
Subject: Re: Forcing exceptions on NANs with GNAT?
Date: Thu, 20 Nov 2008 08:19:56 -0800 (PST)
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Date: 2008-11-20T08:19:56-08:00
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On Nov 20, 3:09 am, Markus Schoepflin <nos...@no.spam> wrote:
> Platform: Linux
> Compiler: GCC/GNAT 3.4.3
>
> Hello,
>
> is it possible to influence the behaviour of GNAT regarding the handling of
> NANs? (Most importantly in the special case of division by zero.)
>
> We need to get exceptions whenever a NAN is generated, is this possible
> somehow? (For example by setting Machine_Overflow to True and recompiling
> the compiler itself.)

I really don't know that much about GNAT, but do those operations
cause SIGFPE signals to be generated, and if so, can they be caught by
an interrupt handler (see C.3)?  And can that handler raise an
exception that is propagated to the program (task) that performed the
operation?

                               -- Adam